So you end up with the pillow section as big as a beach ball and impossible to lie on comfortably... guilty here!

Also guilty. If I have to sleep on an inflatable mattress I'd blow it so tight it's uncomfortable to lie on, can't help myself. One of these times it's going to pop in the night.

Also can't help topping up any soft inflatables that I find. Once I found a slightly flat beachball at someone's house when I was left alone for 10 minutes. I kept telling myself to stop but it ended up way overinflated. I was going to let some air out before closing the valve but it looked so nice I didn't. Left it bulging in the corner. Wonder if anyone noticed. It was rock hard so they would of been curious as to how that happened.

I like them wrinkle free, but slightly soft with rippled seams is more pleasing on the eye.

I can remember one year we were in Benners for a week and we had this clear Bestway pool relaxer lounger where the tubes were heat stretched, and further over inflated to nearly six inches diameter and the back rest took on the appearance of a small beach ball. Where we’d threw a towel over part of it looked a little more normal looking- but for the fact it was starting to bend upwards like a banana. By the end of our weeks stay the vinyl was very thin but we never actually popped it. We just passed it on to a family that we’re checking in down in the hotel lobby as we were heading homewards. Usually we pop them on our last night n leave the remains in the apartment ;D

I'll inflate not just my beach balls, but any PVC inflatable to a rock hard state. With my life-size inflatable bat-mans and spidermans, they're great when they are firm and stiff. I just have to be mineful of the Sydney weather that often alternates between cool and hot over summer. I may inflate something quite firm when it's somewhat cool, but have to note to let some air out when it warms up as the air expands and then may burst the seams, as already they are past the normal inflation pressure. This is particularly so with the life size figures as they are about $50 each, but I'm more adventurous with beach balls as they are much cheaper. With my 36" and 42" balls I'll blow them until the wrinkles are gone from the seams and go somewhat further. The real test is when the valve is done up, bouncing them once or twice off the wall. When it comes back as a nice rapid horizontal bounce with a twang, I'm happy.